JOURNAL OF MOLECULAR STRUCTURE
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2021
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IF 3.196
Jingyan Zhu,Baolin Liu,Weibing Zhang,Jun Jiang,Xinhua Li
Single-molecule magnets in cobalt clusters is much less well known than it is in manganese(II)/(III)/(IV) clusters. To explore new types of cobalt clusters and their potential applications, a new mixed valence coordination polymer ([Co(III) 3 Co(II) 2 (mba) 6 (Hdtba) (H 2 O) 4 ] n , H 2 dtba=2,2’-dithiodibenzoic acid, H 2 mba=2-mercaptobenzoic acid) ( 1 ) is constructed by employing cobalt chloride hexahydrate and H 2 mba as starting reactants under hydrothermal conditions. Single-crystal XRD studies indicate that 1 consists of a trinuclear cobalt(III)-sulfur cluster moiety and two discrete cobalt(II) nodes, which result in the formation of a covalent three-dimensional complex network. Similarly, the cobalt(III) cluster moiety acts as a building unit in this infinite coordination polymer 1 instead of the discrete and tiara-like clusters previously reported in the literature. Magnetic studies show its slow magnetic relaxation in the absence of an applied dc field, which is characteristic behavior of single-ion magnets, caused by the individual Co(II) ions.
研究领域:
无机化学
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材料科学
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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2024
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IF 8.1
Bincheng Xu,Zexi Luo,Tao Tao,Ying Wang
Co-based nanomaterials have been proven as excellent catalysts in activating peroxymonosulfate (PMS), owing to the high adsorption ability and efficient electron transfer toward PMS molecules. However, the slow Co sites regeneration induced by HSO 5 − /SO 5 – redox cycle alone not only deteriorates the utilization efficiency of PMS, but also restricts the overall catalytic reaction rate. Herein, we report a novel S-FeCoO nano-catalyst to active PMS for chloramphenicol (CAP) degradation. As a result, up to 97.73 % of removal efficiency was achieved within 30 min even with an initial CAP concentration of 50 mg/L, which is substantially superior to other Co or Fe-based PMS activation systems. More importantly, synergistic effects arising from the coexisting Fe and S species were identified by the control experiments and characterization results. Co served as the primary active site, while Fe(II) and S 2− /S 2 2− greatly accelerated Co(III)/Co(II) redox cycle by donating electrons. The proposed strategy of dual acceleration of Co(III)/Co(II) redox cycle, as well as its mechanism insights, is expected to provide important implications on the rational design of advanced catalysts for PMS activation.
研究领域:
环境科学
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催化化学
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产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR STRUCTURE
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2021
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IF 3.196
Jin-Juan Xing,Ping-Ping Sun,Yu-Hang Zhang,Xian-Yi Zhao,Fa-Nian Shi
ABSTRACT Three Co (III) complexes based on double ligands {[Co(2,2’-bpy)(2,5-HPda) (2,5-Pda)]Cl·2H 2 O, namely Co-1; [Co(2,2’-bpy)(2,5-Pda) 2 ]·2H 2 O, namely Co-2; [Co(2,2’-bpy)(2,5-HPda)(2,5-Pda)]NO 3 ·H 2 O, namely Co-3} were synthesized by hydrothermal methods. Single crystal X-ray diffraction (XRD), X-ray photoelectron spectrometer (XPS) and energy dispersive spectrometer (EDS) were applied to confirm the components of the three complexes and the oxidation states of the central atom. Optical micrograph, powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FT-IR) and ultraviolet-visible spectrum (UV-vis) were used to characterize these complexes. The thermal stabilities of the three complexes were further evaluated by thermo gravimetric analysis (TG). Afterwards, Co-3 was calcined under a flow of nitrogen at 420 °C for 2 h and the composites (C(N,O)/Co x O y ) were formed. When the composites were used as electrode materials for supercapacitors, the results showed an excellent specific capacitance of 544 F·g −1 in 6 M KOH solution at a current density of 2 A·g −1 . The cycle tests showed that the specific capacitance retained well after 2000 cycles at 20 A·g −1 current density.
研究领域:
材料化学
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能源科学
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DOI
高影响因子
JOURNAL OF MOLECULAR STRUCTURE
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2026
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IF 4.9
Hao Ai,Qiushuo Li,Huaqiao Lu,Lei Xu,Yaofa Gao,Qiong Wu
Minimal structural intervention strategy that achieves exceptional thermal stabilization without altering the core coordination framework. • Mechanistic understanding of how halogen substitution enhances supramolecular packing and electronic stabilization. • Practical blueprint for designing thermally robust molecular materials for applications in catalysis, optoelectronics, and molecular devices. Achieving a precise enhancement in the thermal stability of molecular materials without significantly compromising their inherent coordination architectures remains a formidable challenge, because conventional modifications often require extensive framework reconstruction. Herein, we demonstrate a minimal structural intervention strategy in which a single halogen perturbation drastically enhances the thermal robustness of Co(III)-Schiff-base complexes. By combining crystallographic analysis, variable-temperature X-ray diffraction, and extensive theoretical calculations, we evaluate the mechanistic impact of bromine substitution. The incorporation of a single bromine site remarkably delays the onset decomposition temperature from ca. 100 °C to 250 °C without altering the core coordination framework. Specifically, the high polarizability of bromine increases the global dispersion energy from -207.49 to -235.31 kcal/mol and significantly lowers the LUMO level, thereby creating an internal radical/hot-electron trap. This dual supramolecular and electronic stabilization raises the lattice-disruption energy to approach the cleavage energy of intramolecular covalent bonds. As a result, the thermal breakdown pathway shifts from stepwise dissociation to concerted collapse, offering a practical blueprint for the design of exceptionally stable molecular materials. Download: Download high-res image (348KB) Download: Download full-size image
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高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
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2023
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IF 9.8
Xiaodan Zhao,Jiahui Wei,Ying Wu,Zuoming Zhou,Guohua Jing
Sulfite autoxidation in combination with the cobalt-based heterogeneous activators, has recently emerged as the efficient sulfate radical (SO 4 •− ) generation process for organic micropollutant abatement in the water and wastewater treatment , yet the sluggish >Co(II)/Co(III) redox cycling currently compromises the efficacy of radical generation and the potential applications. Herein, regarding that the reductive W(IV) species in WS 2 can modulate the >Co(II)/Co(III) redox cycling in the advanced oxidation processes , confinement of cobalt with WS 2 (Co-WS 2 ) is designed and characterized. The Co-WS 2 /sulfite process achieves an ultrafast tetracycline (TC) abatement (∼100 % abatement of TC within 1 min) under circumneutral conditions with lower dosage of sulfite and activator, outperforming the current cobalt-based heterogeneous counterparts. The dominant reactive radicals are identified as SO 4 •− and hydroxyl radical (HO • ), which are quantified to be 9.7 μM and 4.5 μM, respectively. The superior radical generation efficiency and the concomitant TC abatement rely on the excellent redox properties and electron transfer capability of Co-WS 2 . The inter-transformation of >Co(II)/>Co(III) can be accelerated via the involvement of the reductive W(IV) species with the redox-reversibility of the W(IV)/W(VI) couple in the presence of sulfite. The TC degradation intermediates and the corresponding pathways are also proposed according to the ultra-performance liquid chromatography and quadrupole-time of flight mass spectrometry (UPLC-QTOF-MS) analysis. In addition, the influences of the reactant dosage, coexisting anions (HCO 3 − , HPO 4 2− , Cl − and NO 3 − ), humic acid and the various real water matrices on TC abatement are thoroughly explored. Especially, the Co-WS 2 /sulfite process is advantageous owing to the negligible effect of the coexisting anions on the TC abatement. This study provides a novel heterogeneous activator for significantly improving sulfite activation efficacy to achieve the efficient organic micropollutant abatement.
研究领域:
环境科学
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化学工程
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DOI
高影响因子
Surfaces and Interfaces
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2024
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IF 5.7
Yitong Guo,Yukai Chang,Libo Wang,Qixun Xia,Aiguo Zhou
In this work, two−dimensional Mo 2 CT x MXene pillared with transition metal complexes [Fe(III), Co(III), or Ni(II)] was prepared, which shows ultra−high performance as the anode of lithium−ion batteries (LIBs). Firstly, Mo 2 CT x was pretreated with hexadecyl trimethyl ammonium bromide (CTAB) as a surfactant and then mixed with hydrated chloride (FeCl 3 ·6H 2 O, CoCl 2 ·6H 2 O, or NiCl 2 ·6H 2 O) at room temperature. The molar ratio of MXene to hydrated chloride was 1:1. In this process, metal ions (Fe 3+ , Co 2+ , or Ni 2+ ) were successfully loaded on the nanosheets of Mo 2 CT x . The ions were combined with the surface terminated oxygen of MXene to form transition metal complexes by liquid phase agitation method. Moreover, transition metal complexes contribute a portion of their capacity and help Mo 2 CT x enhance its own capacity to a large extent. However, the electrochemical effects on Mo 2 CT x vary depending on the type of transition metal ions. As anodes of LIBs, the final discharge specific capacities after 100th cycles at 2 A g −1 were 511.68 mAh g −1 , 229.22 mAh g −1 and 78.19 mAh g −1 for Fe(III)@Mo 2 CT x , Co(III)@Mo 2 CT x , and Ni(II)@Mo 2 CT x , respectively, while the capacity of pure Mo 2 CT x after delamination was only 31.17 mAh g −1 . At 6 A g −1 , the final discharge capacity of Fe(III)@Mo 2 CT x was 227.4 mAh g −1 after 500th cycles. Therefore, Mo 2 CT x MXene pillared by the complexes, especially Fe(III) complexes, is a promising anode material with high−performance for lithium−ion batteries.
研究领域:
材料科学
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电化学
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能源存储
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DOI
高影响因子
International Journal of Electrochemical Science
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2023
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IF 1.5
Zhihong Yan,Hong Li
A Cobalt (III) trisphenanthroline complex ([Co(phen)3] 3+ ) has been adsorption assembled on a glassy carbon electrode (GCE) modified with DNA decorated with graphene oxide (GO) by multiple sweep voltammetry. In the present protocol, GO is served as a functional unit of DNA to greatly improve the efficient immobilization of DNA on the GC electrode and also offer a favorable microenvironment to keep the DNA structure of double-stranded (dsDNA), which facilitates the intercalation of redoxactive [Co(phen)3] 3+ . The evidences from scanning electron microscope, X-ray diffraction, cyclic voltammetry, electrochemical impedance spectroscopy, emission spectroscopy and differential pulse voltammetry reveal that [Co(phen)3] 3+ can be assembled on the surfaces of GO-decorated dsDNA driven by electrostatic attraction, intercalation and π-stacking interaction. Furthermore, the highly stable [Co(phen)3] 3+ /GO-dsDNA/GCE is used to the highly selective determination of 6- mercaptopurine (6-MP) in the human blood with satisfactory. The reduction peak current was linear to 6-MP concentration in the range from 5×10 -8 to 2×10 -6 M 6-MP, and the detection limit is 1.5×10 -8 M ( S / N = 3)
研究领域:
分析化学
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电化学
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纳米材料
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生物传感器
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DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2024
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IF 20.2
Zihao Wan,Minghao Xu,Liang Zhou,Ya Zhang,Xuerui Yang,Sen Lin,Jean-Marc Chovelon,Lei Zhou
In this study, a novel strategy for selectively generating Co(IV)=O species during peroxymonosulfate (PMS) activation was proposed, utilizing an optimized Co 4 Cu 1 -layered double hydroxide (LDH) material with low-coordination and high-spin-state Co sites. The incorporation of Cu(II), influenced by the Jahn-Teller effect, altered the geometry and coordination at Co(III) sites, optimizing the filling of Co 3d orbitals. The Co 4 Cu 1 -LDH/PMS system demonstrated exceptional catalytic activity for degrading emerging contaminants (ECs) across various water matrices, with a high concentration of Co(IV)=O generation. Continuous flow experiments showed an average 97.51 % degradation over 10 hours, indicating significant practical potential. Mechanistically, enhanced performance was attributed to a single electron transfer process and optimized orbital configurations for oxygen ligands at Co(III) sites. This study offers both theoretical insights and practical guidance for developing efficient catalysts targeting Co(IV)=O species in Fenton-like systems.
研究领域:
环境科学
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催化化学
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DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
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2024
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IF 10.8
Yongguang Bu,Wenjing Yu,Qiang Yang,Wenkai Zhang,Qingyu Sun,Wensu Wu,Peixin Cui,Chao Wang,Guandao Gao
Electroreduction of nitrate (NO3RR) to ammonia in membraneless electrolyzers is of great significance for reducing the cost and saving energy consumption. However, severe chemical crossover with side reactions makes it challenging to achieve ideal electrolysis. Herein, we propose a general strategy for efficient membraneless ammonia synthesis by screening NO3RR catalysts with inferior oxygen reduction activity and matching the counter electrode (CE) with good oxygen evolution activity while blocking anodic ammonia oxidation. Consequently, screening the available Co–Co system, the membraneless NO3–-to-NH3 conversion performance was significantly higher than H-type cells using costly proton-exchange membranes. At 200 mA cm–2, the full-cell voltage of the membraneless system (∼2.5 V) is 4 V lower than that of the membrane system (∼6.5 V), and the savings are 61.4 kW h (or 56.9%) per 1 kg NH3 produced. A well-designed pulse process, inducing reversible surface reconstruction that in situ generates and restores the active Co(III) species at the working electrode and forms favorable Co3O4/CoOOH at the CE, further significantly improves NO3–-to-NH3 conversion and blocks side reactions. A maximum NH3 yield rate of 1500.9 μmol cm–2 h–1 was achieved at −0.9 V (Faraday efficiency 92.6%). This pulse-coupled membraneless strategy provides new insights into design complex electrochemical synthesis.
研究领域:
电化学
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催化
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能源效率
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材料科学
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产品关联
DOI
PubMed
高影响因子
Molecular Catalysis
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2025
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IF 4.9
Hang Zhao,Xiuying Liu,Siyu He,Mingxia Guo,Yuhan Huang,Yifan Niu,Haiqing Jiang,Qian Li
Advanced oxidation processes (AOPs) are effective approaches for the removal of organic contaminants from water. In this study, a combined hydrogen peroxide-bicarbonate (H 2 O 2 -HCO 3 − ) oxidant system was engineered for a Fenton-like process catalyzed by lithium cobalt oxide (LCO). The oxidant system integrates hydrogen peroxide oxidation with bicarbonate's dual functionality as both an H 2 O 2 activator and pH buffer. Efficient contaminant degradation was achieved by the LCO/H 2 O 2 HCO 3 − system under neutral or weakly alkaline conditions, and the solution pH remained stable throughout the reaction, due to the presence of HCO 3 − . A comprehensive investigation into the optimization of reaction parameters governing the removal of a phenothiazine dye was conducted. The mechanism driving the generation of reactive oxygen species (ROS) which are responsible for the degradation of organic contaminants was elucidated. These ROS were identified as superoxide radicals, singlet oxygen, and hydroxyl radicals. The Co(III)/Co(II) redox pair in LCO served as the key active sites for activating the H 2 O 2 HCO 3 − . In addition, a possible pathway of the degradation of the phenothiazine structure was proposed based on ultraviolet-visible spectroscopy and liquid chromatography-mass spectrometry analysis. The LCO/H 2 O 2 -HCO 3 − system shows great promise as a sustainable Fenton-like approach for wastewater treatment, with cost-effectiveness, high efficiency, environmental friendliness, and compatibility with neutral or weakly alkaline conditions.
研究领域:
环境化学
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材料科学
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水处理技术
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催化
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化学工程
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产品关联
DOI
高影响因子
INORGANICA CHIMICA ACTA
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2024
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IF 2.7
Hou Cong Li,Ye Fan Zheng,Ming Zhu Wang,Chen Chen Geng,Min Hou,Chang Qing Liu,Wen Ge Li
Two new ligands, 2-(5,6-dihydrobenzo[4,5]imidazo[1,2-c]quinazolin-6-yl)phenol (H 2 L1′) and 2-(5,6-dihydrobenzo[4,5]imidazo[1,2-c]quinazolin-6-yl)-4-fluorophenol (H 2 L2′) were synthesized by 2-(2-aminophenyl)benzimidazole with salicylaldehyde and 5-fluorosalicylaldehyde, respectively. While the two ligands (H 2 L1′ and H 2 L2′) were coordinated with nickel (II) and cobalt (II) ions and represented open-chain Schiff base structures (H 2 L1 and H 2 L2). Their metal complexes: [Ni 2 (HL1) 2 (C 2 H 5 OH) 2 Cl 2 ]‧2C 2 H 5 OH (complex 1), [Co (HL1) (L1)] (complex 2), [Ni 2 (HL2) 2 (C 2 H 5 OH) 2 Cl 2 ]‧2C 2 H 5 OH (complex 3) and [Co (HL2) (L2)] (complex 4) were obtained by solvothermal reaction. The four Schiff base complexes were characterized by infrared spectroscopy, elemental analysis, thermal stability analysis, X-ray powder diffraction, single-crystal X-ray diffraction, and lipophilicity assay. Single crystal X-ray analysis reveals that complexes 1 and 3 crystallize in a monoclinic system with space group P 21/n, while complexes 2 and 4 crystallize in a trigonal system with space group R -3. The lipophilicity assay (Log P) showed that the introduction of fluorine atoms enhanced the lipophilicity of ligands and complexes. The MTT method was used to determine the IC 50 values of complexes, ligands, and cisplatin against four different tumor cells (A-549, SMMC-7721, MDA-MB-231, and CNE-2Z) and one normal cell (IOSE 80). The results indicated that the four complexes exhibited stronger anticancer efficacy than ligands, among which the fluorine-substituted Co (III) complex (complex 4) displayed greater cytotoxicity compared with cisplatin in inhibiting SMMC-7721, MDA-MB-231 cells and A-549 cells, respectively. In addition, complex 4 can increase intracellular reactive oxygen species levels, arrest cells in the G0/G1 phase, upregulate Bax levels, and downregulate Bcl-2 levels, inducing MDA-MB-231 cell apoptosis in a dose-dependent manner.
研究领域:
化学
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医学
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肿瘤学
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DOI
高影响因子
危险品化学品经营许可证（带存储）